1. Field of the Invention
The present invention relates to outline definition apparatuses used to generate outlines which define boundary lines between first-level regions and second-level regions and outline definition methods, and relates to image processing apparatuses. More particularly, the present invention relates to an outline definition apparatus which defines an outline not in units of pixels but with high precision by generating boundary lines defining boundaries between first-level areas and second-level areas in pixels and linking the generated boundary lines.
2. Description of the Related Art
In general, in a field of image processing, a technique in which positions of edge of objects (hereinafter, referred to as “edge positions”) in still images are detected has been used for various purposes. For example, Japanese Unexamined Patent Application Publication No. 8-36641 discloses a method for coding image data with a high coding rate not by coding image data itself but by coding edge data obtained by successively detecting edges of the image data. Furthermore, for example, Japanese Unexamined Patent Application Publication No. 2004-79970 discloses a method for detecting edge positions (mark positions) from an image captured using a CCD (charge coupled device) camera when an overlapping state of circuit patterns is detected using overlapping marks in the course of fabrication. In the detection of the edge positions, for example, pixel portions having data values significantly changed are detected.